Solo Leveling Novel Volume 5 was written by Chugong.

Jinwoo’s received some amazing gifts from the system, but the latest one might prove to be the greatest one yet-a key to the double dungeon where it all started. Perhaps a second visit might provide him with answers for once. He’s got some time to kill until he can use the item though, but before he can tackle another gate, unexpected movement from the shadow soldiers guarding Jinah sets his alarm bells ringing...